Trip-free switch mechanism comprising a latch carried by a thrusttransmitting cam



May 2, 1950 D 2,506,270 TRIP-FREE SWITCH MECHANISM COMPRISING A LATCH -TRANSMITTING CAM CARRIEDBY A THRUST 2 Sheets-Sheet 1 Filed March 20, 1947 INVENTOR 3m 5-, M B

A ORNEY May 2, 1950 2,506,270

TRIP-FREE SWITCH MECHANISM COMPRISING A LATCH CARRIED BY A THRUST-TRANSMITTING CAM 2 Sheets-Sheet 2 Filed March 20, 1947 A ORNEY Patented May 2, 1950 UNITED STATES TENT OFFICE TRIP-FREE SWITCH ING A LATCH CAR TRANSMITTING C MECHANISM COMPRIS- RIED BY A THRUST- AM Application March 20, 1947, Serial No. 736,063

5 Claims.

This invention relates in general to improvements in switch-operating mechanisms, and more particularly to a trip-free mechanism adapted for manual actuation of a switch of the contactor type.

It is an object of the present invention to provide an improved trip-free switch-operating mechanism involving a minimum number of parts.

Another object of the present invention is to provide an improved trip-free switch mechanism in which all parts are always exposed for inspection.

Another object of the present invention is to provide an improved trip-free switch mechanism in which all parts are always accessible.

Objects and advantages other than those above set forth will be apparent from a consideration of the following description when read in connection with the appended drawing, in which:

Fig. 1 is a view in front elevation of one embodiment of the present invention adapted for manual actuation of a switch of the contactor type, showing the elements thereof in the position reached thereby in response to electrical tripping operation;

Fig. 2 is a view in side elevation of the embodiment illustrated in Fig. 1, some of the elements of the actuating mechanism and of their support being assumed removed to clarify the drawing;

Fig. 3 is a view similar to Fig. 2 showing the elements of the mechanism in position for tripfree closure of the switch;

Fig. 4 is a view similar to Fig. 2 showing the elements of the mechanism in the position reached thereby when the switch reaches the closed position; and

Fig. 5 is a view similar to Fig. 2 showing the elements of the mechanism in the position reached thereby when the switch has been tripped manually.

Referring more particularly to the drawing by characters of reference, numeral 6 generally designates a switch of the contactor type mounted on an insulating panel 1. Switch 6 may be of any known type and may comprise a fixed contact 8 resiliently mounted on a bracket 9 supported on panel 1. A cooperating movable contact I is rigidly mounted on an arm I l fastened to a shaft 12. Contact i9 is biased toward the open position shown in Fig. 1 by suitable means, uch as a spring l4 urging arm ll against a suitable stop (not shown). Shaft I2 is supported in a suitable number of bearings I mounted on panel 1.

The actuating means for switch 6 comprise an operating handle !6 mounted on a shaft H. The outer end of the shaft is supported in a bearing [8 which may be mounted on any suitable support such as a cubicle wall I 9. The inner end of shaft l! is preferably pivoted on a pin 2| inserted in a bore provided in the adjacent end of shaft I2.

Shaft l'l carries a stop block 22 and may be rotated in both directions from the position shown to an extent limited by engagement of the stop block with the front surface of panel 3. Shaft I! is biased toward the position shown by means of a torsion spring 23. The spring is provided with extension which straddle a lug 24 mounted on hearing l8 and may alternately be engaged by a pin 25 mounted on shaft I1. Elements I 8, I9, 23, 24 and 25 are shown only on Fig. 1.

The operative connection between shafts i2 and I1 is effected by a linkage comprising a driving crank 26 mounted on shaft I! and a driven crank 21 mounted on shaft 12. The two cranks may be connected through a thrust-transmitting linkage comprising a pin 28 fastened on crank 26 and a cam 29 consisting of a pair of identical pieces of sheet metal disposed on both sides of crank 21.

For closing switch 6, thrust may be transmitted between cranks 26 and 2'! through pin 28 and a cam surface 3|. Cam 29 is also provided with a cam surface 30 to be engaged by pin 29 to cause manual tripping of switch 6. Cam 29 is pivotally connected with crank 27 through a pin 33 and is urged away from its thrust-transmitting position into the position shown in Fig. 2 by means of a spring 32.

Cam 29 may be moved into thrust-transmitting position with respect to crank 26 by tripping means comprising suitable current responsive means such as a solenoid 35. The solenoid is provided with an armature 36 having a limited stroke, which carries a pin 31 retained in an arcuate slot 38 of cam 29.

Cam 29 carries a latch 39 pivoted thereon by means of a pin 40 and resiliently urged against a stop 4| by a spring 42. Latch 39 extends through a window provided in panel 1 and is adapted to catch on a fixed hook 43 mounted on panel 1 to hold switch 6 in closed position.

Figs. 1 and 2 show the elements of the mechanism after tripping has been effected by deenergizing solenoid 36. Armature 36 is in the deactuated position shown, and cam 29 is moved out of thrust-transmitting position into a position determined by thestroke of solenoid armature 36. If handle I6 is then moved in either direction of rotation, the movement of the handle is stopped by engagement of stop block 22 with the surface of panel 1 before pin 28 can engage any surface of cam 29.

To close switch 6, solenoid 35 must first be energized. The solenoid attracts its armature 36, which lifts pin 31. The pin causes cam 29 to 5 pivot about pin 33 into the position shown in Fig.

3, which is the thrust-transmitting position with respect to crank 26. The center of the arcuatee edges of slot 38 is thereby moved to a position on V the common axis of shafts I2 andli'l. i0

When handle it is moved clockwise agains the action of spring 23, pin 28 first travels freely and thereafter engages camsur-face 3i.--Fur-- ther movement of handle it causes crank Zfi to drive crank 2? into actuated position through 15 pin 28 and cam 29 to bring switch Q into the; closed position shown in Fig. l. During such movement, cam 29 is continuously supported on pin 3'! through the upper edge of slot 38 and slides, on the pin. Cam. 2% and :-cranks 7 25, 21,20 then .move as if they were rigidly united..-.:. To ward theend of such movement, latch ,39 rides a over the edge oi hook while pivoting about: pin fl to compress spring,,2. When cam 39 reaches the position shown inFig. 4, springrlz, 2.5 urges latch t9 againststop 4! in a pOSltlOHiiD whichthe latch catches on l1ook; c3. Whem handle 16 is released and. is returned by spring. 23 finto the position, shown in Fig 2, theelements oi the mechanism notrigidly, connected ,39 therewith remain in the position shown in Fig. 4.

When switch .5 is. closed, the switch may, =be,l. tripped by d eenergi zing solenoid Armature 36 drops into thefposition shown inFig. 2 under the action or" avity and of .spri 32,,acting thereonthrough cam 29. ffhe cam pin 33,"thereby raising latch r'i il out o eng e v mentwith"hooked: spings id and r return the eleinents'of the mechanism into the position shown in Fig. 2,

T @1 04 d i ei Y-. moving'handle iii counterclockwise oi-the pp;

siti'onjs'hown in Fig' 5. During such. i overnent, pin 28'first travels freely 'andtl ereafter engages surface so of cam 29., Further. move nentoihandle 1% causes.pivotalrnovement oimam 2,9 about pin The'cam forces armature 36 down. ward against the action of solenoide-iand raises, latch 35? out of engagement with hook. Spring I4 then moves sw itch],,into the.opeh..nosition. As a result thereof, crank 2 moves camiifi into? the position shown in Fig. 5, in'whichpos I slot 38 raised, sufficiently, to .enable armature; 35 to, return toithe, tt w th handleii spri'rigjfiii t 4 elements of the the ed Lrle on remain Fig. It 'llbe apparent that ..if. sol

' a time during clos V a g A ditch" ii, a nature{i5 inrrnediately dropscaus s arn to pivot about pin n tting; postion i if us than handle veer easethe position shown in trated in F 2 to. open switch 6. 111 c switch is therefore tr p-free inaliitspositions, ,Jm Although out oneembodirnent ci-,.the present invention has been iilustrated-and described, it, w l b a pa ntto one skilled in, the art.. that various changes and modifications maybe made therein without departing from the spirit of the 75 for moving saidcam about said pivotal connection into thrust-transmitting position with respect to said driving crank, a latch mounted on said cam, and a fixed hook engaged by said latch in response to movement of said cam into said -thrust-transinitting position and movement of said driving crank bringing said driven crank into actuated position 2. A switch operating mechanism comprising a driving-crank, a driven crank, a cam having a pivotal connection with said driven crank and being actuable into-a thrust-transmitting position with respect tossaidgdriving;crank;aalatch== mounted on said icam; a fixedhook engaged byx: said latch. in response to movement or" said .cam into said thrust-transmitting position and movee; ment; of said driving crank bringingisaidd-riven crank intoactuated position, and" current, re;-. sponsive means: for, causing .movement: of said I cam about said pivotal connection out of said; thrust-transmitting portion to disengage said latch from said hook. r1: 22.: 1

3. A; switch operating mecr anism comprising a driving crank, a driven crank, a cam havinga. p ota o nec io with: s ididriven: crank, icura rent: mmm em a s. connected: with; said :camfor moving said-earn abou-t said pivotal 0011:1809, tion into thust transmittng position-with .re-; spect o; driving c ra nk, a latch mounted ionic Said am nd a x hoo e ed y; said l tch in response -to;;movement ofsaid caminto saidai thrust-transmitting position and movement of, said driving crank bringing said dr iveg1;crank intoactuated positi n, said cam beingqprovidedo witha cam surface engaged by said driving crank. upon reversal ofsaid movement.oisaid-driving, crank into tripping position to cause movement of 1 said cam about said pivotalr-connection to;.dis engage saidJatc-h from said hookiagainst th action of said currentresponsive means;

4.. A;..switch operatin mechanism comprising actuating means, a linkage .operatively connected?- to said actuating means,,a crank .operativelycon-i. nected to said linkage, tripping means ionholde ing, said linkage in a positionfoiytransmi-ttingr thrustirorn said actuating Ineansto, said crank through said linkage, latch rnounted on said. linkage, and a fixed hook engagedby saidlatch. in responseto movement of said crank into actuated position. i

A,.swii h.,ope at n mechanismcomp isin i a driving crank, a driven crank mounted..on an... shait, a cam mounted on said driven crank and, having pivotal connection therewith at a point remote from saidshait, and current responsive cam about said pivotal connection into a position 5 for transmitting thrust from said driving crank to said driven crank through said cam.

RQY F. KIDD:

rannwons orran ,7 H The following references are of record the v) file of this patent: i UN'rrEnsYrtATj 's' Prairies Number.

Name- Date Meter et a1. Jan. 3, 1911 

